High-power laser systems are being developed for a number of military and commercial applications. However, at high average output powers, problems associated with a lasing medium in a laser system are exacerbated. These problems include stress in the mounting of the lasing medium, inefficient and non-uniform cooling of the lasing medium, inefficient coupling of pumplight into the lasing medium, and inefficient coupling of laser beams into and out of the lasing medium.
Low-efficiency cooling may cause an unacceptable rise in the average temperature of the lasing medium relative to an inlet temperature of a coolant. Mounting stress and non-uniform heating can create phase distortions in an amplified output beam and can lead to damage or even fracturing of the lasing medium, which can also damage nearby elements of the laser system. Inefficient coupling of pumplight into the lasing medium can lead to overall laser inefficiencies, and stray pumplight can cause damage to the lasing medium or other elements of the laser system. Stray input or output laser beams can damage elements of the laser system, and the loss of power detracts from a total output power and an overall laser efficiency of the laser system.